Fair Billing is a Java program designed to calculate the total duration and number of sessions for users based on session start and end times provided in a log file. It is particularly useful for hosted application providers who charge based on session duration.
- Parses session start and end times from a log file.
- Calculates the total duration and number of sessions for each user.
- Handles cases where session start or end times are missing or incomplete.
- Produces a report showing user names, session counts, and total durations.
- Java 17 or higher
- Maven for building the project
- Log file containing session start and end times (in the format HH:MM:SS)
-
Navigate to the project directory:
cd fair-billing -
Build the project and run tests using Maven:
mvn clean install
This will create a JAR file in the target directory.
ls target
-
Run the program with the path to the log file as a command-line argument:
java -jar target/fair-billing.jar /path/to/logfile.log
Replace
/path/to/logfile.txtwith the path to your log file. -
View the generated log file (fairbilling.log) in root showing user names, session counts, and total durations.
The Fair Billing API is a Spring Boot application that provides a REST API for calculating the total duration and number of sessions for users based on session start and end times provided in a log file.
This endpoint calculates the total duration and number of sessions for each user based on session start and end times provided in a log file.
logFilePath: The path to the log file. This is a required parameter.
The response is a list of UserBilling objects. Each UserBilling object contains the following fields:
username: The username of the user.totalSessions: The total number of sessions for the user.totalBillableSeconds: The total duration of all sessions for the user in seconds.
Request:
GET /api/fair-billing?logFilePath=/path/to/logfile.log
Response:
[
{
"username": "ALICE99",
"totalSessions": 4,
"totalBillableSeconds": 240
},
{
"username": "CHARLIE",
"totalSessions": 3,
"totalBillableSeconds": 37
}
]If the logFilePath parameter is not provided or the file cannot be read, the API will return a 400 Bad Request status code with an error message.
To run the Spring Boot application, you can use the Spring Boot Maven plugin:
mvn spring-boot:runThis will start the application on port 8080. You can then access the API at http://localhost:8080/api/fair-billing.
Pre-requisites: Docker installed on your machine/vm.
To run the Java application in a Docker container, follow these steps:
Build the Docker image using the following command in the same directory as the Dockerfile:
docker build -t <image-name> .
Replace with the desired name for your Docker image.
Run the Docker container using the following command:
docker run -p 8080:8080 <image-name>
Replace with the name you specified in earlier step.
This will start your Java application within a Docker container, making it easy to deploy and run in any environment that supports Docker.
Refer to the example log file below:
14:02:03 ALICE99 Start
14:02:05 CHARLIE End
14:02:34 ALICE99 End
14:02:58 ALICE99 Start
14:03:02 CHARLIE Start
14:03:33 ALICE99 Start
14:03:35 ALICE99 End
14:03:37 CHARLIE End
14:04:05 ALICE99 End
14:04:23 ALICE99 End
14:04:41 CHARLIE Start
A log file (fairbilling.log) will be generated in the root directory showing the following output:
2024-05-16 23:05:27,225 INFO c.b.u.FairBillingUtils [main] ALICE99 4 240
2024-05-16 23:05:27,230 INFO c.b.u.FairBillingUtils [main] CHARLIE 3 37
The output shows the user name, session count, and total duration for each user. It also logs any lines that are ignored due to incorrect formatting.
2024-05-16 23:06:18,706 ERROR c.b.u.FairBillingUtils [main] Ignoring line: 14:02:05 CHARLIE Enddddddd
2024-05-16 23:06:18,712 ERROR c.b.u.FairBillingUtils [main] Ignoring line: 14:02:34 ALICE@99 End
2024-05-16 23:06:18,712 ERROR c.b.u.FairBillingUtils [main] Ignoring line: 14:03:33 ALICE!99 Start
2024-05-16 23:06:18,712 ERROR c.b.u.FairBillingUtils [main] Ignoring line: 14:03:35 ALICE$99 End
- The log file follows chronological order based on time.
- The log file contains logs for one day only.
Example for an error log file that contains logs for two days:
23:52:15 EMILY Start
23:52:20 OLIVIA End
00:51:12 SAMUEL Start
00:51:18 EMILY End
00:51:25 OLIVIA End
The application uses Log4J for logging. The log file (fairbilling.log) will be generated in the root directory showing the user name, session count, and total duration for each user. It also logs any lines that are ignored due to incorrect formatting.
The log4j2.xml file in the resources directory contains the configuration for Log4J. You can modify this file to change the logging level, output format, and log file location.
The project includes JUnit tests to verify the functionality of the FairBillingUtils class. You can run the tests using Maven:
mvn test** Negative test cases are also included to test the handling of invalid log file entries.
The project includes a GitHub Actions workflow that runs the Maven build and test process whenever a push is made to the main branch. The status of the workflow can be viewed in the Actions tab of the GitHub repository.
Refer .workflow/ for the workflow configuration.
The project includes a GitHub Actions workflow that builds the project, runs unit tests, and generates a Docker image whenever a new release is created. The status of the workflow can be viewed in the Actions tab of the GitHub repository.
The project includes a GitHub Actions workflow that builds a Docker image and pushes it to Docker Hub whenever a new release is created. The status of the workflow can be viewed in the Actions tab of the GitHub repository.
The project includes a CodeQL workflow that analyzes the codebase for potential security vulnerabilities and coding errors. The status of the workflow can be viewed in the Actions tab of the GitHub repository.
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.
This project is licensed under the MIT License - see the LICENSE file for details.